Federal NDP Leader Jack Layton died today, just months after leading his party to unprecedented success in the federal election campaign. He was 61.

The party issued a statement from Layton’s family.

“We deeply regret to inform you that The Honourable Jack Layton, leader of the New Democratic Party of Canada, passed away at 4:45 am today, Monday August 22,” said the statement from his wife, Olivia Chow, and two children, Sarah and Michael.

“He passed away peacefully at his home surrounded by family and loved ones.”

Funeral details were not immediately announced.

Condolences began to pour in, often through social media.

Gov. Gen. David Johnston first commented on Twitter:

“I learned with great sadness we just lost Jack Layton. Our thoughts are with his family and friends.”

Bob Rae, a former NDP premier of Ontario and now federal Liberal leader, also sent a tweet:

“Deeply saddened by news about Jack Layton, Arlene and I send deepest condolences to Olivia and family. He is a loss to a grieving Canada.”

New Democrat MP Jagmeet Singh was on Twitter:

“Dear Jack Layton — the inspiration that you are is unparalleled. Your legacy will live on — we promise!”

Layton’s death came a month after he appeared at a news conference, looking frail and gaunt, to announce he was suffering from a new, unspecified cancer and would temporarily step down as party leader and head of the official Opposition.

Nycole Turmel, a rookie Quebec MP and veteran labour leader, took over within days, but the caucus and party all expressed hope for Layton’s quick return to health.

It was not to be.

Layton had been diagnosed with prostate cancer in early 2010, but continued a crowded schedule while getting treatment. He suffered a hip fracture just before the start of the spring campaign but it was surgically repaired. He leaned on a cane during the campaign, but seemed as full of energy and optimism as ever.